U.S. patent number 10,588,679 [Application Number 15/521,742] was granted by the patent office on 2020-03-17 for compression fixation system.
This patent grant is currently assigned to NUMAGENESIS, LLC. The grantee listed for this patent is Lawrence Binder, Robert Kukla, NUMAGENESIS, LLC, Marc Von Amsberg. Invention is credited to Lawrence Binder, Robert Kukla, Marc Von Amsberg.
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United States Patent |
10,588,679 |
Kukla , et al. |
March 17, 2020 |
Compression fixation system
Abstract
The invention is directed in various aspects to a compression
fixation system that includes coupling components and locking
assemblies for connecting two or more separate elements in a fixed
arrangement. For example, the system is useful for connecting and
compressing two or more elements selected from bones and bone
fragments. The system includes a substantially linear coupling
component, such as, for example, a Kirschner Wire ("K-Wire") and
locking assembly elements that engage with the coupling component
in a coaxial orientation. The coupling component includes at least
a linear portion and an anchor portion, the anchor portion
configured to be fixed within or adjacent to a first one of the
elements to be connected and the linear portion configured to be
fixed adjacent to a second one of the elements to be connected,
where the locking assembly is attached coaxially with and locked
against the second element to achieve compression and fixation.
Inventors: |
Kukla; Robert (Hickory, NC),
Von Amsberg; Marc (Waxhaw, NC), Binder; Lawrence (Miami,
FL) |
Applicant: |
Name |
City |
State |
Country |
Type |
NUMAGENESIS, LLC
Kukla; Robert
Von Amsberg; Marc
Binder; Lawrence |
Hickory
Hickory
Waxhaw
Miami |
NC
NC
NC
FL |
US
US
US
US |
|
|
Assignee: |
NUMAGENESIS, LLC (Hickory,
NC)
|
Family
ID: |
55858457 |
Appl.
No.: |
15/521,742 |
Filed: |
November 2, 2015 |
PCT
Filed: |
November 02, 2015 |
PCT No.: |
PCT/US2015/058670 |
371(c)(1),(2),(4) Date: |
April 25, 2017 |
PCT
Pub. No.: |
WO2016/070191 |
PCT
Pub. Date: |
May 06, 2016 |
Prior Publication Data
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|
|
Document
Identifier |
Publication Date |
|
US 20170238983 A1 |
Aug 24, 2017 |
|
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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62073968 |
Nov 1, 2014 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B
17/68 (20130101); A61B 17/885 (20130101); A61B
17/8869 (20130101); A61B 17/8866 (20130101); A61B
17/683 (20130101); A61B 17/8872 (20130101) |
Current International
Class: |
A61B
17/88 (20060101); A61B 17/68 (20060101) |
References Cited
[Referenced By]
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Other References
Cachia, V.V., et al., Mechanical Characteristics of the New
BONE-LOK Bi-Cortical Internal Fixation Device, Nov./Dec. 2003,
344-349, vol. 42, No. 6, The Journal of Foot & Ankle Surgery,
California. cited by applicant .
Notification of Transmittal of the International Search Report and
the Written Opinion of the International Searching Authority, or
the Declaration for corresponding application PCT/US2019/030654,
filed May 3, 2019. cited by applicant.
|
Primary Examiner: Gibson; Eric S
Attorney, Agent or Firm: McNees Wallace & Nurick LLC
Parent Case Text
RELATED APPLICATIONS
This application is a 35 USC 371 National Stage application that
claims priority to PCT/US2015/058760 filed on Nov. 2, 2015, which
application claims the benefit under 35 U.S.C. .sctn. 119 (e) to
U.S. Provisional Application Ser. No. 62/073,968 filed Nov. 1,
2014, the entireties of which are incorporated herein by reference.
Claims
The invention claimed is:
1. A compression fastener system comprising: a coupling component
having proximal and distal ends, a locking assembly, and an anchor
component that is integral with the coupling component at the
coupling component's distal end, wherein the anchor component is a
toggle, the locking assembly engageable with the coupling component
and comprising at least a first compressible collet, and at least a
first collet compression component; wherein the locking assembly,
when assembled, may be provisionally locked to enable free linear
movement along the coupling component.
2. A compression fastener system according to claim 1, the coupling
component comprising an elongate wire, the locking assembly also
comprising a second collet compression component.
3. A compression fastener system according to claim 2, the first
collet compression component comprising a collet seat that receives
and is engageable with the compressible collet, and the second
collet compression component comprising a compression nut that is
engageable with the collet seat and is actuatable between
provisionally locked and locked configurations, wherein each of the
compressible collet, collet seat and compression nut are generally
cylindrical and when assembled share a common center axis, and
wherein the collet is engageable and compressible directly with the
coupling component.
4. A compression fastener system according to claim 3, wherein
engagement between the components is achieved by one of press
fitting and threaded engagement between the collet seat and the
compression nut.
5. A compression fastener system according to claim 4, wherein the
toggle is engageable with the coupling component in a cantilever
pivotal arrangement, such that in one configuration, the toggle is
pivoted into linear alignment with the coupling component and is
nested within a recess therein, and in a second configuration, the
toggle is deployed in a generally perpendicular orientation
relative to the axis of the coupling component, and wherein the
engagement between the locking assembly is by threaded engagement
between the collet seat comprising interior threads and a threaded
compression nut comprising corresponding threads for engagement
with the collet seat.
6. A compression fastener system according to claim 5, wherein at
least one of (i) at least a portion of an outer surface of the
distal end of the coupling component and (ii) at least a portion of
an inner face of the compressible collet comprises a surface
feature selected from one or a combination of ridges, grooves,
keels, fins, threads, dimples, knurls, and surface texturing, and
wherein the surface features of the at least one of the outer
surface of the coupling component and the inner face of the
compressible collet cooperate with the opposing surface of the
assembly when the locking assembly is in a locked configuration to
enhance the compressive securement of the locked compression
fixture system.
7. A compression fastener system according to claim 6, wherein each
of the at least a portion of an outer surface of the distal end of
the coupling component and at least a portion of an inner face of
the compressible collet comprises a surface feature.
8. A compression fastener system according to claim 7, wherein the
compressible collet is selected from (i) unitary slit form that
comprises at least one slit selected from a through slit and a
partial slit, and (ii) a multi piece form.
9. A compression fastener system according to claim 2, wherein the
first collet compression component operates to retain the
compressible collet, and wherein the second collet compression
component operates in engagement with the first collet compression
component in a first configuration to provisionally secure the
locking assembly to the coupling component and in a second
configuration to fixedly secure the locking assembly into
compression locking with the coupling component.
10. A compression fastener system according to claim 9, the first
collet compression component comprising a flexible securement ring
that is engageable with the compressible collet, and the second
collet compression component comprising a locking cap that is
engageable with the compressible collet and the securement ring,
and actuatable between provisionally locked and locked
configurations, wherein each of the compressible collet, securement
ring and cap are generally cylindrical, and wherein the
compressible collet is engageable and compressible directly with
the coupling component, and wherein when the locking assembly and
the coupling component are assembled they share a common center
axis, and wherein engagement between the components is achieved by
press fitting.
11. A compression fastener system according to claim 10, wherein
the toggle is engageable with the coupling component in a
cantilever pivotal arrangement, such that in one configuration, the
toggle is pivoted into linear alignment with the coupling component
and is nested within a recess therein, and in a second
configuration, the toggle is deployed in a generally perpendicular
orientation relative to the axis of the coupling component.
12. A compression fastener system according to claim 11, wherein at
least one of (i) at least a portion of an outer surface of the
distal end of the coupling component and (ii) at least a portion of
an inner face of the compressible collet comprises a surface
feature selected from one or a combination of ridges, grooves,
keels, fins, threads, dimples, knurls, and surface texturing, and
wherein the surface features of the at least one of the outer
surface of the coupling component and the inner face of the
compressible collet cooperate with the opposing surface of the
assembly when the locking assembly is in a locked configuration to
enhance the compressive securement of the locked compression
fixture system.
13. A compression fastener system according to claim 12, wherein
each of the at least a portion of an outer surface of the distal
end of the coupling component and at least a portion of an inner
face of the compressible collet comprises a surface feature, and
wherein the securement ring comprises silicone.
14. A compression fastener system according to claim 13, wherein
the compressible collet is selected from (i) a unitary slit form
that comprises at least one slit selected from a through slit and a
partial slit, and (ii) a multi piece form.
15. A compression fastener system according to claim 9, wherein the
locking assembly and the coupling component are preassembled in a
provisionally locked configuration, the assembly further comprising
an insertion tool that is engageable with the provisionally locked
assembly, the insertion tool comprising nesting elongate inner and
outer sleeves, the outer sleeve adapted to engage with one of the
compressible collet and the first and second compression components
and the inner sleeve adapted to engage with the other of the
compressible collet and the first and second compression
components, the inner and outer sleeves releasably engageable
between free and limited degrees of freedom around and along a
shared center axis, wherein when the inner and outer sleeves are
not engaged, one of the sleeves is actuatable along the axis to
direct translation of the assembly distally, and wherein when the
inner and outer sleeves are engaged, at least one sleeve is
actuatable either around or along the axis to drive fixed
engagement between the first and second compression components.
16. A compression fastener system according to claim 15, the first
collet compression component comprising a flexible securement ring
that is engageable with the compressible collet, and the second
collet compression component comprising a locking cap that is
engageable with the compressible collet and the securement ring,
and actuatable between provisionally locked and locked
configurations, wherein each of the compressible collet, securement
ring and cap are generally cylindrical, and wherein the
compressible collet is engageable and compressible directly with
the coupling component, and wherein when the locking assembly and
the coupling component are assembled they share a common center
axis, and wherein engagement between the components is achieved by
press fitting, wherein the toggle is engageable with the coupling
component in a cantilever pivotal arrangement, such that in one
configuration, the toggle is pivoted into linear alignment with the
coupling component and is nested within a recess therein, and in a
second configuration, the toggle is deployed in a generally
perpendicular orientation relative to the axis of the coupling
component wherein at least one of (i) at least a portion of an
outer surface of the distal end of the coupling component and (ii)
at least a portion of an inner face of the compressible collet
comprises a surface feature selected from one or a combination of
ridges, grooves, keels, fins, threads, dimples, knurls, and surface
texturing, and wherein the surface features of the at least one of
the outer surface of the coupling component and the inner face of
the compressible collet cooperate with the opposing surface of the
assembly when the locking assembly is in a locked configuration to
enhance the compressive securement of the locked compression
fixture system, wherein each of the at least a portion of an outer
surface of the distal end of the coupling component and at least a
portion of an inner face of the compressible collet comprises a
surface feature, and wherein the securement ring comprises
silicone, wherein the compressible collet is selected from (i)
unitary slit form that comprises at least one slit selected from a
through slit and a partial slit, and (ii) a multi piece form,
wherein the inner sleeve of the insertion tool engages with the
compressible collet and the outer sleeve engages with the locking
cap, and wherein upon engagement of the sleeves the outer sleeve is
actuated by displacement in a distal direction to lock the locking
cap to the securement ring and thereby compress and lock the
compressible collet into compressive engagement with the coupling
component.
17. A compression fastener system according to claim 15, the first
collet compression component comprising collet seat that receives
and is engageable with the compressible collet, and the second
collet compression component comprising a compression nut that is
engageable with the collet seat and is actuatable between
provisionally locked and locked configurations, wherein each of the
compressible collet, collet seat and compression nut are generally
cylindrical and when assembled share a common center axis, and
wherein the compressible collet is engageable and compressible
directly with the coupling component, wherein engagement between
the components is achieved by one of press fitting and threaded
engagement between the collet seat and the compression nut, wherein
the toggle is engageable with the coupling component in a
cantilever pivotal arrangement, such that in one configuration, the
toggle is pivoted into linear alignment with the coupling component
and is nested within a recess therein, and in a second
configuration, the toggle is deployed in a generally perpendicular
orientation relative to the axis of the coupling component, and
wherein the engagement between the locking assembly is by threaded
engagement between the collet seat comprising interior threads and
a threaded compression nut comprising corresponding threads for
engagement with the collet seat, wherein at least one of (i) at
least a portion of an outer surface of the distal end of the
coupling component and (ii) at least a portion of an inner face of
the compressible collet comprises a surface feature selected from
one or a combination of ridges, grooves, keels, fins, threads,
dimples, knurls, and surface texturing, and wherein the surface
features of the at least one of the outer surface of the coupling
component and the inner face of the compressible collet cooperate
with the opposing surface of the assembly when the locking assembly
is in a locked configuration to enhance the compressive securement
of the locked compression fixture system, wherein each of the at
least a portion of an outer surface of the distal end of the
coupling component and at least a portion of an inner face of the
compressible collet comprises a surface feature, wherein the
compressible collet is selected from (i) unitary slit form that
comprises at least one slit selected from a through slit and a
partial slit, and (ii) a multi piece form, and wherein the inner
sleeve of the insertion tool engages with the nut and the outer
sleeve engages with the collet seat, and wherein upon engagement of
the sleeves the inner sleeve is actuated by rotation around the
shared axis to drive further engagement of the engaged threads of
the collet seat and the nut in a distal direction to lock the nut
to the collet seat and thereby compress and lock the compressible
collet into compressive engagement with the coupling component.
18. A compression fastener system according to claim 1, wherein the
compression component comprises a securement ring that operates to
retain the compressible collet in a first configuration to
provisionally secure the locking assembly to the coupling component
and in a second configuration to fixedly secure the locking
assembly into compression locking with the coupling component,
wherein each of the compressible collet and the securement ring are
generally cylindrical, and wherein the compressible collet is
engageable and compressible directly with the coupling component,
and wherein when the locking assembly and the coupling component
are assembled they share a common center axis, and wherein
engagement between the components is achieved by press fitting,
wherein, the securement ring comprises a contractile material that
is responsive to application of an activator selected from one or
more of heat, electrical, chemical and mechanical compressive force
such that in a pre activated form, the ring is either or both
pliable and has a circumferential dimension that is greater than
the receiving recess of the compressible collet, and in the
activated form the ring is contracted so that it becomes more rigid
and contracts to assume a smaller circumferential diameter such
that it fits within and compresses against the compressible collet
thereby locking the assembly to the coupling component.
19. A compression fastener system comprising: a coupling component
having proximal and distal ends and an elongate axis, a toggle
anchor affixed to the distal end of the coupling component, the
toggle anchor being pivotal around an axis that is perpendicular to
the elongate axis of the coupling component, and a locking assembly
that is engageable with the coupling component in a co-axial
orientation around the elongate axis of the coupling component, the
locking assembly comprising a compressible collet and a collet
compression component.
20. A compression fastener system according to claim 19, wherein
the coupling component is selected from a wire and a bone pin.
21. A compression fastener system according to claim 19, wherein
the collet compression component is selected from (i) a locking cap
that is engagable with the compressible collet, and (ii) a seat for
retaining the compressible collet, and a compression nut that is
engagable with the seat.
22. A compression fastener system according to claim 21, wherein
the collet compression component is a locking cap that is engagable
with the compressible collet and further comprises a flexible
securement ring that is engageable circumferentially on an outer
surface of the compressible collet, the locking cap being further
engageable with the securement ring.
23. A compression fastener system according to claim 22, wherein
the coupling component is a wire that comprises flexible metal, and
wherein the compressible collet comprises on its outer surface a
circumferential recess for retaining the flexible securement
ring.
24. A method for achieving compression fixation of a plurality of
bone elements, comprising: inserting an elongate coupling component
having distal and proximal ends into a through hole in each of the
bone elements, the bone elements arranged for fixation along a
generally linear path from a proximal position to a distal
position, actuating an anchor at the distal end of the coupling
component into engagement with a distal face of the most distally
positioned bone element, sequentially engaging each of a locking
assembly, and tensioning and insertion tools into engagement with
the coupling component, the tensioning tool engaged fixedly with
the proximal end of the coupling component and also engaged loosely
with a more distal portion of the coupling component; each of the
locking assembly and the insertion tool engaged along an axis that
is shared with the coupling component, the insertion tool
positioned between a more distal engagement position of the
tensioning tool and the most proximally positioned fragment of the
aligned bone fragments, and the locking assembly positioned between
the insertion tool and the most proximally positioned fragment of
the aligned bone fragments, actuating the tensioning tool to
displace the coupling component in a proximal direction thereby
exerting distally directed pressure on the insertion tool whereby
distally directed pressure is also exerted on the locking assembly
to direct the locking assembly into compressive contact with the
most proximally positioned fragment, and actuating the insertion
tool to engage the locking assembly into a locked configuration.
Description
FIELD OF INVENTION AND BACKGROUND
The invention relates generally to a locking assembly and a
compression fixation system for fixing two or more elements
together and to maintain, and optionally adjust a desired degree of
compression across the two or more objects. The system is suitable,
for example, for connecting and compressing two or more elements
selected from bones and bone fragments. The system includes a
substantially linear coupling component, and a locking assembly
that engages with a locking assembly-receiving portion the coupling
component in a generally coaxial orientation.
The invention is described herein below in relation to bone
fractures, which is but an example of the useful application of the
invention. One skilled in the art will appreciate that the locking
assembly and compression fixation system components and the methods
of use thereof as described herein can be used without undue
adaptation for applications that include, but are not limited to:
connecting one or more medical devices or appliances to bone;
connecting one or more medical or other devices together; repairing
structural components, for example, household, building and
construction components such as combinations of two or more pieces
of wood, concrete, supports, beams, studs, joists, columns, wall
boards; and the like.
Devices and systems as disclosed herein are useful for a variety of
applications, including with particularity, orthopedic fixation.
There are many needs in orthopedics for the fixation of bones. In
some instances, adjacent bones must be fixed together to allow for
healing of damaged associated soft tissue, or to replace the
function of such soft tissue, such as in the case of ligament
damage between adjacent bones as well as tendon damage. In other
instances, fractures of bones must be corrected by alignment,
reduction of space between, and compression of the bone fragments
to enable bone healing. Many approaches are known in the medical
arts for achieving the attachment, fixation, and desired degrees of
compression of bones and bone fragments. Generally, for example,
threaded screws with and without heads, pins and rods, and wires
may be used. There are challenges with all of these, which include,
for example, imprecise compression and fixation, protrusion of the
fixation element from bone into tissue (screw heads, twists of
wires), bone loss/damage due to size of fixation element and damage
to bone (for example, thread stripping of screws within bone), and
costs associated with inventory to provide the number of components
needed to meet size ranges of fractures.
Included in the art are several examples of compression bone
fixation systems that are aimed at overcoming the shortcomings of
wires and screws for bone fixation. In many instances, such systems
provide fixation that overcomes some of the limitations of bone
screws and wires. However, it remains a problem in the art to
achieve fixation of relatively small bones using low profile
fixation components that are capable of fine adjustment to
placement and tensioning, are relatively simple to manipulate and
are adjustable and/or removable post fixation.
Accordingly, there is a need for a fixation system that can fix,
align and compress bone elements together wherein the system
presents minimal risk of bone compromise and loss, and provides
ease of use by the clinician, adjustability in size to minimize
inventory needs, and highly reliable and precise and reversible
locking to achieve reliable fixation and enable the clinically
needed degree of compression between bone elements. Indeed, a
particular advantage of the inventions provided herein is
overcoming the challenges presented in the art with implant
placement and subsequent adjustment or removal.
BRIEF DESCRIPTION OF THE DRAWINGS
Features and advantages of the general inventive concepts will
become apparent from the following description made with reference
to the accompanying drawings, including drawings represented herein
in the attached set of figures, of which the following is a brief
description:
FIG. 1 shows a side view of a first embodiment of a fully assembled
compression fixation system engaged with coupling component
tensioning and insertion tools;
FIG. 2 shows in the left panel an enlarged perspective view of an
embodiment of a fully assembled compression fixation system engaged
with coupling component locking assembly insertion tools, and in
the upper right panel a close up perspective view of respective
embodiments of a coupling component, and in the lower right panel
an anchor and an anatomically correct model of a foot with a
metatarsal fracture that is fixated with an embodiment of a
compression fastening system according to this disclosure;
FIG. 3 shows alternate front, side, back, perspective, bottom, side
and top views of an embodiment of a coupling component;
FIG. 4 shows in the upper left panel alternate front, bottom, side,
top, side, perspective and end views of the embodiment of the
anchor shown in FIG. 2 the anchor comprising a toggle, and in the
bottom left and right panels, respectively, cross sectional side
views of respective embodiments of the anchor and coupling
component;
FIG. 5 shows in the upper left panel a close up perspective view in
color of the compression fixation assembly in an open
configuration, and in the upper right panel a close up of the
locking assembly, and in the lower left panel an enlarged cutaway
perspective view of a locking assembly in a locked configuration
engaged with a coupling component of the compression fixation
assembly, and in the lower right panel, an enlarged side view of
the embodiment of a fully assembled compression fixation system
engaged with coupling component locking assembly;
FIG. 6 shows in the upper left panel side views of alternate split
and slit embodiments of locking collets, and in the middle left
panel cross sectional side views of alternate smooth and textured
embodiments of locking collets, and in the lower left panel an
embodiment of a locking assembly cap on the left and an embodiment
of a securement ring on the right; in the upper right and lower
right panels, respectively, show alternate open and locked
configuration views of the locking assembly embodiment;
FIG. 7 shows in the left panel alternate front, perspective, top,
side bottom, back, side, and bottom views of a split embodiment of
a locking collet, and in the right panel alternate front,
perspective, top, side bottom, back, side, and bottom views of a
slit embodiment of a locking collet of the locking assembly;
FIG. 8 shows in the top panel alternate cross sectional side and
perspective views of a locking cap, and in the middle panel,
alternate top, side, bottom and side views of a locking cap, and in
the bottom panel, alternate side, top/bottom, and perspective views
of a securement ring of the locking assembly;
FIG. 9 shows in the upper panel, a perspective view of an
embodiment of assembled insertion tools, and in the lower left and
right panels, respectively, perspective views of the disassembled
outer and inner sleeve components of the insertion tools;
FIG. 10 shows in the left panel a cross sectional perspective view
of the assembled insertion tools, and in the right panel, an cross
sectional side view of the embodiment of a fully assembled
compression fixation system engaged with coupling component locking
assembly;
FIG. 11 shows alternate top, side, front, side, back, bottom and
perspective views of the outer sleeve of the insertion instrument
shown in FIG. 9;
FIG. 12 shows alternate top, perspective front, side, back, side
and bottom views of the inner sleeve of the insertion instrument
shown in FIG. 9;
FIG. 13 shows alternate top, perspective front, side, back, cross
sectional side, and bottom views of the inner sleeve of the
insertion instrument shown in FIG. 9;
FIG. 14 shows enlarged alternate perspective views of the assembly
shown in FIG. 1, the left panel showing the engagement of the
tensioning instrument with the coupling component pre-tensioned,
and the right panel showing the same assembly after an actuation of
the tensioning instrument;
FIG. 15 shows alternate views of a tensioning instrument, the upper
left panel showing a top view of the instrument, the upper right
panel showing a side view, the middle panel showing a close up view
of the coupling component engagement features, the lower left and
right panels showing respective front end and back end perspective
views of the tensioning instrument;
FIG. 16 shows in the upper panel a side view of a second embodiment
of a fully assembled compression fixation system engaged with
coupling component tensioning and insertion tools, and in the lower
left panel a side view of the locking assembly and coupling
components, and in the lower right panel a bottom perspective view
of the locking assembly and coupling components;
FIG. 17 shows various views of components of an alternate exemplary
embodiment of a locking assembly, including in the upper and middle
panels, respectively, solid and cross sectional views of a collet
(left), a collet seat (center), and a compression nut (right), and
in the lower left panel the exemplary locking assembly assembled
with the coupling component inserted through the central bore, and
in the right panel the assembled locking assembly components form a
channel there through for receiving a coupling component to achieve
locking fixation with the coupling component;
FIG. 18 shows in the upper left panel an end view of the counter
torque insertion tool engaged with an assembled locking assembly,
showing the edges of the opposing pins, and in the upper right and
lower left panels alternate cross sectional views of the assembly,
and in the lower right panel a cutaway view of the outer sleeve of
the counter torque insertion tool showing in a depicted embodiment
opposing pins that are press fit into the outer sleeve;
FIG. 19 depicts respectively in the upper left, upper right, lower
left and lower right panels alternate embodiments a compression
fixation system comprising an first end having a anchor and a
second end having a locking compression means for securing and
locking an elongate coupling component; and,
FIG. 20 depicts respectively in the upper left and upper right
panels alternate embodiments a compression fixation system
comprising an first end having a anchor and a second end having a
locking compression means for securing and locking an elongate
coupling component, and in a lower panel an alternate embodiment of
an anchor component.
Features and advantages of the general inventive concepts will
become apparent from the following description made with reference
to the accompanying drawings, including drawings represented herein
in the attached set of figures, of which the following is a brief
description:
This disclosure describes exemplary embodiments in accordance with
the general inventive concepts and is not intended to limit the
scope of the invention in any way. Indeed, the invention as
described in the specification is broader than and unlimited by the
exemplary embodiments set forth herein, and the terms used herein
have their full ordinary meaning.
DESCRIPTION
This description describes exemplary embodiments in accordance with
the general inventive concepts and is not intended to limit the
scope of the invention in any way. Indeed, the invention as
described in the specification is broader than and unlimited by the
exemplary embodiments set forth herein, and the terms used herein
have their full ordinary meaning.
The general inventive concepts will now be described with
occasional reference to the exemplary embodiments of the invention.
Unless otherwise defined, all technical and scientific terms used
herein have the same meaning as commonly understood by one of
ordinary skill in the art encompassing the general inventive
concepts. The terminology set forth in this detailed description is
for describing particular embodiments only and is not intended to
be limiting of the general inventive concepts.
As used herein, the singular forms "a," "an," and "the" are
intended to include the plural forms as well, unless the context
clearly indicates otherwise. The term "proximal" as used in
connection with any object refers to the portion of the object that
is closest to the operator of the object (or some other stated
reference point), and the term "distal" refers to the portion of
the object that is farthest from the operator of the object (or
some other stated reference point). The term "operator" means and
refers to any professional or paraprofessional who delivers
clinical care to a medical patient, particularly in connection with
the delivery of care. More broadly, in connection with non-medical
uses of the inventions described herein, the term refers to a user
of one or more components of the compression fixation system.
Unless otherwise indicated, all numbers expressing quantities,
properties, and so forth as used in the specification and claims
are to be understood as being modified in all instances by the term
"about." Accordingly, unless otherwise indicated, the numerical
properties set forth in the specification and claims are
approximations that may vary depending on the suitable properties
desired in embodiments of the present invention. Notwithstanding
that the numerical ranges and parameters setting forth the broad
scope of the general inventive concepts are approximations, the
numerical values set forth in the specific examples are reported as
precisely as possible. Any numerical values, however, inherently
contain certain errors necessarily resulting from error found in
their respective measurements.
Use of Compression Fixation System
Generally in accordance with the embodiments described herein and
depicted in the drawings, the invention is directed in various
aspects to systems, components, instruments, and methods for fixing
and/or compressing elements along a generally rectilinear path,
using at least one of each of a coupling component and a locking
assembly. As described herein, the locking assembly and the
coupling component engage in a generally coaxial orientation, such
that, at least a portion of the coupling component comprises a
generally rectilinear configuration and is adapted to engage with
the locking assembly.
In certain particular embodiments, the system enables fixation of
two or more traumatized, fractured, deformed, and/or otherwise
displaced bones or bone fragments. Embodiments of compression
fixation systems are disclosed herein that significantly enhance
the surgical techniques for repairing damaged bones, such as
fractured phalangeal and metatarsal bones, and provide improved and
superior performance in the achievement and maintenance of fixation
and desired bone compression as compared with use of conventional
wires and screws. For example, in contrast to screws, certain
embodiments of the systems described herein enable flexible and
adjustable orientation and positioning of adjacent bones to be
fixed, which cannot be achieved using conventional rigid screws. In
particular, the adaptable sizing of the coupling components enables
customized sizing without the need to have a wide array of sizes on
hand such as is required when using screws. That is, the coupling
components are adaptable for use with different locking assemblies,
and the coupling components can be adjusted in a length dimension,
thus obviating the need for alternate lengths. And in another
example, in contrast to conventional K (Kirschner) wires which are
also used in the medical arts for bone fixation whereby they are
fixed into compression via crimping and twisting, certain
embodiments of the systems described herein enable precise
compression that can be finely and selectively adjusted without
compromise to the healing bone or to the fixation system
components. Moreover, the instant disclosure enables use of
ancillary fixation devices such as flanges and plates that can be
positioned and locked to bone using the adjustable locking
assemblies described herein.
Significant benefits can be realized in connection with surgical
use of the fixation system, including, but not limited to:
optimized patient experience and outcome as a result of controlled
and precise compression to enhance healing and minimized bone
damage/loss; improved time efficiency during surgery; and enhanced
options for implant selection and customization. Time savings
during surgery are realized in comparison to the current state of
the art due to the elimination of need to precisely measure for and
select a specific length of implant; the instant disclosure
provides a system that can be customized in size without any
compromise in fixation. Cost savings can also be realized through
reduction of required implant sizes; the instant disclosure
provides a system in which one implant fits all and can be easily
sized to the specific patient, resulting in a significant reduction
in the number and size of devices that must be stocked.
While the examples provided herein pertain to the
fixation/compression of bone material, it will be appreciated that
other materials of relevance to the body, including biological and
non-biological, implanted and non-implanted, can be fixed together
and as desirable, compressed using the inventions disclosed herein.
Examples herein include use of the compression fixation system for
reduction, alignment, fixation and/or compression of bone fragments
such as in the phalanges and metatarsal bones. Of course, it will
be appreciated by one skilled in the art that the inventive
components can be used in connection with most types of fractures,
particularly such fractures that are typically treated by
percutaneous insertion of pins and wires and screws. Further, the
system is suitable for use with other bone element fixation
indications.
Components, Instruments and Techniques for Compression/Fixation
Example 1: Snap Fit Compression Fixation System 10
Referring now to the drawings, FIG. 1 shows a side view of a fully
assembled compression fixation system 10 engaged with coupling
component 20 tensioning and locking assembly 40 insertion
instruments 70, 80.
The compression fixation system 10 includes a coupling component 20
that is selected from suitable wire and other bone pins and similar
rod type devices, such as, for example K-wire. The coupling
component 20 is adapted at a distal first end 21, intended to be
most distal to the operator, with an anchor portion 23 for fixation
within or on a distal outer surface of a first bone element. The
coupling component 20 is further adapted at a proximal second end
22, intended to be most proximal to the operator, with a locking
assembly 40 receiver portion 24 that is generally rectilinear. In
various embodiments, at least the proximal second end 22 portion of
the coupling component 20 is substantially rectilinear, and
cylindrical, while the distal and a medial portion of the coupling
component 20 may be other than rectilinear or may be initially
rectilinear and manipulated by the operator for optimal engagement
and shape conformity with the two or more elements to be fixed.
The distal anchor portion 23 of the coupling component 20 may be
selected from any of a number of anchors known in the art, and
generally selected from (i) those that are adapted to engage with
and remain substantially within and anchor to a bone, and (ii)
those that extend through bone and are adapted to engage with an
outer surface of a bone or bone fragment, or a plate or other
non-bone material that is intended to be held adjacent to the
distal bone element. Some examples of anchors that are adapted to
engage with and remain substantially within and anchor to a bone
include self or non-self tapping threads, and bone engagement
features that can engage by press fitting such as keels, ribs and
fins. Some examples of anchors that extend through bone and are
adapted to engage with an outer surface include coils, barbs, and
toggles.
Referring now to FIG. 2, an anatomically correct model of a foot
with a metatarsal fracture is shown, wherein the fracture is
fixated with an embodiment of a compression fixation system 10
according to this disclosure. As shown, an untrimmed coupling
component 20 extends proximally out of the upper surface of the
fractured bone, and a locking assembly 40 is fixed on the coupling
component 20 and is in compression against the proximal (upper)
bone element while the anchor (not shown) is oriented opposite from
the locking assembly 40 on the distal side of the distal (lower)
bone fragment to achieve locked fixation between the bones.
One of ordinary skill will appreciate that the depicted coupling
component 20 can be provided in variable lengths, with or without
curves or bends, with or without surface texture and/or surface
features. Moreover, while the depicted coupling component 20 is
generally cylindrical in shape from the proximal end and terminates
at the exemplary anchor, one of ordinary skill will appreciate that
the shape may be other than cylindrical (i.e., the cross section
may be other than circular). Thus, in some alternate embodiments,
the coupling component 20 may have a cross section that is selected
from one of the following non-limiting examples, including,
scalloped, star shaped, hexagonal, square, and ovoid. Likewise, the
coupling component 20 may be uniform in cross sectional shape and
width along its entire length, or it may comprise regions that vary
and include combinations of different cross sectional shapes,
widths/diameters, and textures.
Thus, it will be appreciated that any particular portion of a
coupling component 20 which may be substantially rectilinear for
receiving a locking assembly 40 may be cylindrical or otherwise
shaped and may be smooth or have any one of a variety of surface
features 26 such as grooves or notches and textures that comprise
knurling or other non-smooth texturing. Further, while the
exemplary embodiment of the coupling component 20 shown in the
drawings terminates as a cylinder at the proximal end, there may be
alternate shapes and features at the proximal end that are suited
for engagement with a tool or instrument. Thus, in some
non-limiting examples, the coupling component 20 may comprise at
its proximal end a hemispherical, conical or frustoconical feature,
or a star, scallop or hex cross-section, or combinations of
these.
Referring now to FIG. 3, alternate views of an embodiment of a
coupling component 20 are shown, and in FIG. 4 cross sectional
views of the distal first end 21 portion of a coupling component 20
and a detached toggle anchor 30 are shown. In the depicted
embodiment, the coupling component 20 comprises a series of spaced
circumferential grooves along at least a portion of its length, the
grooves adapted for receiving one or more ridge features on the
inner surface of a locking assembly 40. It will be appreciated that
in some embodiments, the number and spacing of the grooves may vary
such that there are more or fewer, the grooves are narrower or
wider, deeper or shallower, and are equidistant or variably spaced.
In addition, in alternate embodiments, a coupling component 20 may
comprise other surface features 26 to either enhance sliding
between a coupling component 20 or to enhance friction there
between. Further, such textures and features may vary along the
length of a coupling component 20 to differentially enhance surface
contact with various instruments, collet compression locking
components, and bone.
In some alternate embodiments, the coupling component 20 may have a
diameter that permits cannulation through at least a portion of the
coupling component 20. In some examples such embodiments would
include cannulated bone wires and pins. In other such embodiments,
examples include tubes, conduit, pipes, and other substantially
hollow components that are suitable to receive a locking assembly
40 along at least a portion of the component that is
rectilinear.
Referring again to the drawings, enlarged views of the distal first
end 21 portion of an exemplary embodiment of a coupling component
20 are shown in FIG. 2. As depicted, the anchor is a toggle anchor
30, which is pivotal around an axis that is perpendicular to a long
axis of the coupling component 20. In the depicted embodiment, the
toggle anchor 30 is pivotal in only one direction, the coupling
component 20 being adapted to receive the toggle anchor 30 into a
recess 27 that receives a portion of the toggle anchor 30 body 32
whereby the overall cross sectional area of the distal end 33 of
the closed toggle anchor 30 matches the cross sectional area of the
distal portion of the coupling component 20 allowing a minimal
profile for insertion into bone. The cantilever design enables
actuation of the toggle anchor 30 against tissue that is distal to
the most distal bone fragment to facilitate engagement of the
toggle anchor 30 with the bone for achieving fixation between the
bone fragments. Of course, it will be appreciated that other mating
configurations of a toggle anchor 30 and coupling component 20 are
possible.
Referring to FIG. 2, the left panel shows a proximal to distal end
perspective view of the assembly including insertion instruments
with a toggle anchor 30 at the distal end, and FIG. 2 upper right
panel shows a close up alternate distal to proximal end perspective
view of a deployed toggle anchor 30. In each of FIG. 1 and FIG. 2
the toggle anchor 30 is in a securement configuration, such that
the toggle anchor 30 is pivoted so that it is aligned perpendicular
to the long axis of the coupling component 20 to enable securement
against bone through which the assembly is passed. In the insertion
configuration (not shown) the toggle anchor 30 is pivoted 90
degrees so that its axis is in line with the axis of the proximal
end of the coupling component 20, for insertion into the bone and
allowing clean exit from a hole in the bone that traverses the bone
from a proximal to a distal end of the bone.
Actuation of the pivot feature of the toggle anchor 30 rotates its
position so that it is perpendicular to the axis of the coupling
component 20, and is deployed to operate as an anchor, thereby
preventing back out of the coupling component 20 from the bone.
According to the instant embodiment shown in FIG. 2, the toggle
anchor 30 as shown attaches to and engages with the coupling
component 20 in a nested cantilever configuration, whereby
actuation to close the toggle anchor 30 involves pivoting around a
central pivot axis that is on the terminal end along the axis of
the coupling component 20. In alternate embodiments as disclosed
herein, the toggle anchor 30 component is attached in an alternate
manner whereby the coupling component 20 is split at its end, and
the toggle anchor 30 rotates within the split end of the coupling
component 20. And in accordance with the depicted embodiment, the
toggle anchor 30 is attached to the distal end of the coupling
component 20 using a through pin 32 that snap fits or may
alternatively be welded or soldered in place. One of ordinary skill
will understand that yet in other embodiments, the toggle anchor 30
may be attached by any one of other possible means.
In various exemplary embodiments of the locking assembly 40, as
shown in the drawings, inter-engaging compression and collet 50
components cooperate along a shared axis and inter-engage to form a
locking assembly 40. Assembled locking assembly 40 components form
a through channel for receiving a coupling component 20 to achieve
locking fixation with the coupling component 20. According to the
various embodiments, the compression and collet 50 components are
constructed to slide over at least a distal first end 21 of the
coupling component 20 while in an open configuration, can be held
stably on the coupling component 20 in a friction (engaged but not
locked) configuration to enable positioning relative to the
elements to be fixed, and can be actuated to achieve a locked
configuration.
Referring again to the drawings, FIG. 5 shows an exemplary locking
assembly 40 assembled with the coupling component 20 inserted
through the central bore 52, the anchor in the form of a toggle
anchor 30 in the open configuration for fixation to bone. The
depicted embodiment of the locking assembly 40 comprises a collet
50, a securement ring 55, and a locking cap 60. As shown, the
locking cap 60 is shown as transparent to reveal the relative
inter-fitting between the respective collet 50, securement ring 55,
and locking cap 60 components. FIG. 5 upper left panel shows the
locking assembly 40 in an open configuration and FIG. 5 upper right
panel shows the assembly in a locked configuration.
Referring now to FIG. 6, the discrete collet 50, securement ring 55
and locking cap 60 components are shown, wherein with respect to
each of the securement ring 55 and the locking cap 60, the
components are shown with a perspective view from their proximal
faces or tops, while with respect to the collet 50, it is shown
with a perspective view from its distal face or bottom.
An advantageous aspect of this embodiment of the locking assembly
40 is that the connection and compression can be achieved without
introduction of rotational insertion to the system; that is, the
collet 50, securement ring 55 and locking cap 60 are designed to
engage with the by compression and snap fitting, without rotating
around the shared axis with the coupling component 20, thereby
diminishing the risk of material stripping into patient tissue and
ensuring optimal compression and purchase of the coupling component
20 surface. In various embodiments, the compression fixation system
10 may be provided for use by an operator in a pre-assembled state,
completely disassembled, or in a state of sub-assembly.
Referring again to FIG. 6, alternate views of the locking assembly
40 are shown in the right panel, wherein in the top view the
assembly is in an open configuration, and in the lower panel, the
assembly is in a closed, locked configuration. As will be described
further herein, the collet compression locking components are fully
movable along the length of a coupling component 20 while in the
open configuration. According to the instant embodiment, engagement
of the securement ring 55 around the collet 50 provides sufficient
force to maintain the collet 50 in a slightly compressed state,
thereby allowing free movement of the provisionally engaged locking
assembly 40 proximally and distally along the length of the
coupling component 20. Applying axial compression to the locking
assembly 40 results in the translation of the locking cap 60
distally, across the surface of the securement ring 55, whereby it
encloses and compresses the securement ring 55 against the collet
50 to lock the assembly to the coupling component 20. In the closed
configuration, the inner face of the collet 50 is compressed firmly
against the coupling component 20 and this compressive force
retains the position of the locking assembly 40 to maintain
compression on the bone. According to the depicted embodiment as
shown in FIG. 6, for example, the collet 50 is adapted with ridges
on its inner face which are spaced and sized to inter-fit in
corresponding circumferential grooves on the surface of the
coupling component 20. In the closed configuration, the compression
fit of the locking assembly 40 is enhanced through the
inter-engagement between these ridges and grooves.
Of course, as described elsewhere herein, both the collet 50 and
the coupling component 20 may be devoid of any surface features,
wherein retention of the locking assembly 40 would rely on
compressive force alone. And in other embodiments, one or more
interacting surface features on either or both the collet 50 and
the coupling component 20 may be provided to enhance locking.
Notably, according to the embodiment shown in FIG. 6, when the
locking assembly 40 is in the open configuration, the assembly can
be adapted to move in either proximal or distal directions with the
rounded ridges on the collet 50 passing over and across the rounded
grooves on the coupling component 20 to enable precise positioning
of the locking assembly 40 prior to closure. As such, at least in
the depicted embodiments, the assembly can be freely adjusted
without the use of any additional tools such as would be required
with a one way ratcheting mechanism.
In the depicted embodiment of the collet 50, shown, for example, in
FIG. 6, the collet 50, as depicted, is generally cylindrical,
having a central bore 52 that is cylindrical and adapted to receive
the coupling component 20, a tapered distal end that is generally
frustoconical, a cylindrical proximal end, and is adapted in a
center portion of its outer surface with a circumferential recess
53 adapted to receive and retain the securement ring 55. The
locking cap 60 is adapted with internal engagement features to fit
over and engage with the securement ring 55. In the open
configuration, the distal opening of the locking cap 60 rests on
and is provisionally secured to the securement ring 55. In the
closed configuration, the locking cap 60 slides distally towards
the distal end of the collet 50 and thereby encloses the securement
ring 55 and engages with a distal end thereof to close the locking
assembly 40.
Referring again to FIG. 6, the collet 50, as depicted, includes a
generally frustoconical proximal end, with a central bore 52 that
is substantially cylindrical from its proximal to its distal end.
Referring to the upper left panel, two representative alternate
embodiments of collet 50 are shown, wherein one embodiment is
unitary with a single slit 54 from the proximal to the distal end.
In another embodiment as show, the collet 50 is provided in two
halves that are split 56 along the proximal to distal dimension. As
shown in the lower left panel, a first embodiment of a collet 50
has a smooth cylindrical inner face 51, and a second embodiment has
a textured inner face 51 comprising ridges 57. FIG. 7 left panel
shows alternate views of a split collet 50, and FIG. 7 right panel
shows alternate views of a split collet 50. It will be appreciated
by one of ordinary skill that in some yet further embodiments, a
collet 50 may be formed of more than two parts, and yet other
embodiments of slit or slotted collets 50 may be provided. Some
alternate slotting embodiments of collets 50 are described
herein.
According to some embodiments, the collet 50 comprises a series of
spaced circumferential ridges 57 along at least a portion of the
length of its internal face 51 from proximal to distal, the ridges
adapted for resting in one or more groove features 28 on the
surface of a coupling component 20. It will be appreciated that in
some embodiments, the number and spacing of the ridges 57 on the
inner face of the collet 50 may vary such that there are more or
fewer, the ridges are narrower or wider, sharper or shallower, and
are equidistant or variably spaced. In addition, in alternate
embodiments, a collet 50 may comprise no surface features on its
internal face 51, other surface features or combinations thereof to
either enhance sliding between a collet 50 and a coupling component
20 or to enhance friction there between. Further, such textures and
features may vary along the internal face 51 of the collet 50 to
differentially enhance surface contact with a coupling component
20. It will be appreciated by those skilled in the art that other
engagement features are possible and that the disclosed engagement
feature is not to be limiting. In alternate embodiments, all or a
portion of the interior face 51 as well as the exterior surface 58
of the collet 50 may be textured by surface treatment or other
features such as ridges 57, grooves, keels, fins, thread, dimples
and the like to enhance engagement with and locking between the
collet 50 and the coupling component 20.
In alternate embodiments, the collet 50 may extend distally to form
a sleeve that extends along at least a portion of a coupling
component 20 that is inserted there through wherein the length of
the frustoconical portion is greater than in the embodiments shown
in the aforementioned drawings. Referring to the drawings, FIGS. 19
and 20 depict some such embodiments. Of course, in yet other
embodiments, the distal end of the collet 50 may extend along
substantially all of the length of the coupling component 20. In
some such embodiments, a further locking component (not shown) may
be provided which attaches to the distal end of the coupling
component 20 and extends proximally to receive and engage the
distal end of the elongated collet 50. In some such embodiments,
the extended sleeve closely contacts the surface of the coupling
component 20 providing enhanced locking engagement therewith.
According to such specific embodiments, the extended sleeve may be
adapted with a taper to allow insertion into the proximal surface
of the bone to further enhance fixation and securement to the bone.
Optionally, the distal sleeve 90' may have on its exterior surface
features or texture that further enhance engagement with bone,
particularly when the taper is inserted therein.
Referring again to FIG. 6, the securement ring 55 is sized to rest
in the circumferential recess 53 of the collet 50. The securement
ring 55 may be made of a minimally flexible material and used to
act as the primary circumferential retaining force to secure the
collet 50 and its slidable engagement with the coupling component
20, used without the locking cap 60. The securement ring 55 resides
within the circumferential recess 53 of the collet 50 for both the
open and closed configurations of the locking assembly 40, sliding
from a proximal open (provisionally locked) position, and allowing
movement along the axis to a distal closed/locked configuration,
whereby the circumferential diameter compresses the securement ring
55 and the collet 50 into a locked state in compressive
communication with the coupling component 20. According to the
disclosure herein, the securement ring 55 is formed with a material
that is non-elastic to minimally elastic and slipped over the
proximal end of the collet 50 prior to assembly on the coupling
component 20 and will retain close engagement and assembly of
collet 50 embodiments that comprise two or more parts in a
partially or provisionally closed configuration.
In some examples, the securement ring 55 is formed of silicone. In
alternate examples, other suitable materials may be used to provide
the needed elasticity and stiffness. In the various embodiments,
the material, such as silicone, will be compressed by the inference
of the locking cap 60 with the securement ring 55 in the open
configuration to maintain the securement of the locking cap 60, and
will remain sufficiently flexible to prevent compression and
closure of the collet 50. Further, the material will be more fully
compressed when in the closed position, thereby exerting
compressive force on the collet 50 to lock and close it. Thus, the
material is capable of expanding in various directions when under
compressive force, and can act as a spring closure to secure but
not lock the collet 50 except when the fully closed compressive
force of the locking cap 60 is applied. Of course it will be
appreciated that other materials having the desired properties may
be selected and that alternative materials may be selected from
flexible and shape memory metals, such as nitinol, the selection of
material being non limiting.
In yet other embodiments, the securement ring 55 may be formed of a
more rigid material, such as, for example, polymers and metals as
described further herein below, and according to such embodiments,
the securement ring 55 may be segmented, or wound like a spring, or
it may comprise a plurality of circumferentially arranged slits
that confer flexibility and spring like qualities. And in yet other
embodiments, the securement ring 55 may be formed with an array of
multiple securement rings 55 stacked and arranged in the recess of
the collet 50 formed of the same or different materials as
described herein above. And in yet other embodiments, the
securement ring 55 may be formed of a fabric band or a stacked
array of bands. It will be understood that combinations of the
afore described embodiments may be employed to provide a securement
ring 55.
And in further embodiments, the securement ring 55 may be formed of
a contractile material that is responsive to application of an
activator such as heat, electrical, chemical or other force or
means such that in a pre activated form, the securement ring 55 may
be more pliable and or may have a circumferential dimension that is
greater than the receiving recess of the collet 50, and in the
activated form the securement ring 55 is contracted so that it
becomes more rigid and or contracts to assume a smaller
circumferential diameter such that it fits within and compresses
against the collet 50. According to some such embodiments, the
contractile securement ring 55 when activated does not operate to
fully compress the collet 50, and locking of the assembly requires
application of the locking cap 60. According to other such
embodiments, the securement ring 55 functions as both a provisional
and a fix locking component wherein the application of activation
of the contractile securement ring 55 converts it from the
provisional locking (open) configuration to the locked (closed)
configuration, without application of the locking cap 60. Thus,
according to such embodiments, the locking components are fully
movable along the length of the coupling component 20. Engagement
of the securement ring 55 around the collet 50 provides sufficient
force to maintain the collet 50 in a slightly compressed state
thereby allowing free movement of the provisionally engaged locking
assembly 40 proximally and distally along the length of the
coupling component 20. The securement ring 55, residing in a
circumferential recess 53 on the collet 50, and fashioned out of
contractile material which may be activated by heat, electrical,
chemical or other means, can be activated to apply a
circumferential force to the collet 50 whereby it compresses the
securement ring 55 against the collet 50 to lock the assembly to
the coupling component 20.
In various embodiments, the securement ring 55 may be smooth with
rounded edges as depicted in the figures. In yet other embodiments,
the securement ring 55 may be squared at its edges, or may have
combinations of square and rounded edges. Further, in alternate
embodiments one or both of the internal and outer faces of a
securement ring 55 may have features or textures that enhance
engagement with smooth or corresponding features and textures on
the outer face of the collet 50 and on the inner face of the
locking cap 60. Thus, in alternate embodiments, all or a portion of
the interior surface 55b and/or the exterior surface of the
securement ring 55 may be textured with surface treatment or other
features such as ridges, grooves, keels, fins, thread, dimples to
enhance engagement with and locking between the securement ring 55
and either or both the collet 50 and the locking cap 60. FIG. 8
lower panel shows alternate views of a securement ring 55 according
to the embodiment of the locking assembly 40 shown in FIG. 6. In
various embodiments, the securement ring 55 performs the functions
of maintaining provisional closure of the collet 50 in the open
configuration (including also maintaining the contact and assembly
of multi part collet 50), retention of the locking cap 60 while the
assembly is in the open configuration, and providing compression on
the collet 50 and securing the locking cap 60 in the closed
configuration
Referring again to FIG. 6 and FIG. 8, the locking cap 60, as
depicted, has a cylindrical body 61 with cylindrical interior 62
and exterior 63 surfaces, and comprising a circumferential recess
64 on its inner surface defined by ridges 65, 66 on the distal 68
and proximal 67 interior surfaces. Referring now to FIG. 8 upper
and middle panels, alternate views of the locking cap 60 are shown.
As can be seen in the upper left panel, which is a cross sectional
view of the locking cap 60, the proximal interior ridge 66 is
slightly more prominent than the distal interior ridge 65, to
facilitate ease of passage of the distal end 68 of the locking cap
60 over the securement ring 55. As can be seen in the first and
third lower panels, which depict the proximal 67 and distal 68
ends, respectively, the locking cap 60 has a inner diameter that is
greater at the distal end 68 vs. the proximal end 67 to further
ensure that the locking cap 60 can pass over the securement ring 55
and not pass beyond the securement ring 55 distally. In various
embodiments, the locking cap 60 may be smooth with rounded edges as
depicted in the figures. In yet other embodiments, the locking cap
60 may be squared at its outer edges, or may have combinations of
square and rounded edges. Further, in alternate embodiments one or
both of the internal and outer faces 63, 62 of a locking cap 60 may
have features or textures that enhance engagement with smooth or
corresponding features and textures on the outer face of the
securement ring 55. Further, it will be appreciated by one of skill
in the art that the locking cap 60 may be formed as a securement
ring 55 or as a unitary closed locking cap 60 that is engageable
with a collet 50 and securement ring 55 subassembly, thus, the term
used herein to refer to the locking cap 60 is not intended to be
limiting. In alternate embodiments, all or a portion of the
interior and/or the exterior surface 63, 62 of the locking cap may
be textured with surface treatment or other features such as
ridges, grooves, keels, fins, thread, dimples to enhance engagement
with and locking between the locking cap 60 and the securement ring
55.
Example 2: Clinical Technique
In alternate embodiments, one or more adaptations to the locking
assembly 40 and its components are contemplated to enable ready use
with other stabilization implants, such as, for example,
stabilization plates, such as bone plates. In accordance with one
such embodiment, the locking assembly 40 is adapted to be engaged
within a through hole or seat in a stabilization implant, formed
from a metal or other suitable implant material. In various
embodiments, the stabilization implant comprises one or more
locking assembly 40 receiver portions 24 that are shaped and
comprise engagement features, such as threads, for achieving
locking engagement with a locking assembly 40. In an exemplary
embodiment, the seat in the stabilization implant is concave
hemispherical and the outer base of the collet seat 55' is
correspondingly convex hemispherical, and each are threaded for
engagement. In another exemplary embodiment, the seat in the
stabilization implant is a cylindrical through hole and the collet
seat 55' is cylindrically shaped at least at a portion including or
distal to its proximal end and at its distal end, and each is
threaded for engagement.
One of ordinary skill will appreciate that the corresponding shapes
and engagement features may vary. Moreover, it will also be
appreciated that a stabilization implant may comprise one or more
types of engagement features for locking assemblies 40 according to
the instant invention, as well as for fasteners known in the art
such as conventional screws. Further, it will be appreciated that
stabilization implants may be provided preassembled with one or
more locking assemblies 40 according to the instant invention.
In use by an operator, installation of the components of the
exemplary compression fixation system 10 for element fixation,
including bone element fixation as described above, includes
initial selection of a coupling component 20 device that is to be
inserted through the elements to be fixed. An anchor component of
the coupling component 20 is then actuated to engage with the
element that is most distant from the operator, and a locking
assembly 40 is slid over the coupling component 20 in a coaxial
orientation towards the two or more elements and pressed against
the element most proximal to the operator while at the same time
the coupling component 20 is held under tension until the desired
compression is achieved. The locking assembly 40 is then actuated
into a locked configuration relative to the coupling component 20
and the elements, to thereby fix the assembly and maintain the
desired compression.
When the elements being compressed are bone, then, consistent with
suitable clinical practice, the system is retained intact so that
compression is maintained over the clinically appropriate healing
period. In some embodiments, the compression fixation system 10 is
adjusted during the healing to maintain, increase, or reduce
compression. Optionally, the system may be removed from the bone
after healing.
Of course, it will be appreciated that the locking assembly 40 may
be used with other coupling components 20 that lack an anchor and
comprise other features that are not described herein. Indeed, in
some embodiments, the locking assembly 40 may be adapted and scaled
to engage with coupling components 20 that are substantially
smaller than bone pins and wires, and with coupling components 20
that are substantially larger scale. Accordingly, the references to
"proximal" and "distal" in regards to the exemplary coupling
components 20 described herein are not intended to be limiting, and
generically, the orientation of the locking assembly 40 as used
herein and as may be used in other applications is not in any way
limiting.
Example 3: Instruments for Engaging and Tensioning System
Components
The compression fixation system 10 also includes instruments for
assembling and locking the coupling component 20 and locking
assembly 40 components.
One exemplary instrument includes a locking assembly 40 insertion
tool 80, shown in perspective view in FIG. 9. The insertion tool 80
operates to maintain orientation and alignment of the locking
assembly 40 components and the coupling component 20 and can be
actuated to reduce and lock the locking assembly 40 components, or
loosen and unlock the locking assembly 40 for adjustment during
healing or post treatment removal of the system. Referring again to
the drawings, FIG. 9-FIG. 13 show alternate views of the components
of an exemplary embodiment of a locking assembly 40 insertion tool
80 for achieving placement, component reduction, friction
tensioning, locking and unlocking of a locking assembly 40 as
described herein. Referring now to FIG. 9, the insertion tool 80
includes two nesting elongate sleeves 81, 82, each having a
substantially cylindrical interior, the inner sleeve 81 having an
internal and external cylindrical shape and dimensioned to closely
interfit with the cylindrical interior 62 of the outer sleeve 82.
As depicted in FIG. 10, which is a cross sectional view of the
interfitted sleeves 81, 82, the insertion tool 80 includes at least
one pin 83 that may be press fit into the outer sleeve 82. The pin
83 can be actuated to engage with and constrain the outer sleeve 82
to the inner sleeve 81 engagement in a slot 84 in the body of the
inner sleeve 81. Upon engagement of the at least one pin 83, the
outer sleeve 82 is able to freely rotate along the distance of the
slot 84 about the inner sleeve 81. The outer sleeve 82 can also
translate axially relative to the inner sleeve 81, but only a short
distance defined but the proximal and distal boundaries of the pin
83 engagement slot. This distance corresponds roughly to the amount
of translation needed to engage the locking cap 60 to the collet
50. FIG. 11-13 each show in various views each of the outer sleeve
82, the inner sleeve 81, and the assembled insertion tool 80
components.
Referring again to FIG. 10, each of the sleeves 81, 82 of the
depicted locking assembly 40 insertion tool 80 inter-engages with
at least a portion of the external surface of one or more of the
collet 50 and the locking cap 60. The outer sleeve 82 is adapted
with an interior groove 85 feature that inter-engages with the
outer proximal edge of the locking cap 60 to stabilize it relative
to the other components of the locking assembly 40. The inner
sleeve 81 is adapted to inter engage with the proximal
frustoconical end of the collet 50. The engagement there between
enables differential securement of the insertion tool 80 to the
collet 50 to enable downward pressure on the collet 50 for
engagement of the collet 50 with the bone without actuating
downward pressure on the locking cap 60. As further described
herein, use of the tensioning tool first reduces the bone and the
locking component into engagement with the bone. Thereafter,
engagement of the inserter pin 83 enables discrete actuation of the
outer sleeve 82 to compress the locking cap 60 against the collet
50 and securement ring 55 to snugly lock the locking assembly 40 in
tight engagement with the coupling component 20.
Should removal and adjustment of the locking assembly 40 be
required, a flat driver or other instrument can be inserted between
the distal end of the locking cap 60 and the distal edge of the
securement ring 55 recess 64 to disengage the locking cap 60 from
the securement ring 55. In some embodiments, such as shown in FIG.
10, the distal edge of the locking cap 60 and the opposing distal
edge of the recess in the collet 50 may be chamfered to facilitate
insertion of a tool for disengagement. Of course, other instruments
may be used to disengage the locking cap 60 and the collet 50, such
as a circumferential grip that can grasp and pull the components
apart. FIG. 10 right panel shows a cross sectional view of the
insertion instrument inner and outer sleeves engaged with the
compression fixation system 10. As can be seen, the inner sleeve of
the insertion tool 80' is engaged with features of the proximal end
of the collet 50, and the edges of the outer sleeve are engaged
with the outer edges of the locking cap 60.
Another exemplary instrument includes a tensioning instrument 70
that clamps the coupling component 20 to stabilize it and enable
maintenance of tension during locking assembly 40 securement. The
tensioning instrument is shown in FIG. 1 and FIG. 16, for example,
and in various views in FIG. 14 and FIG. 16. Referring to FIG. 1,
the exemplary embodiment of the tensioning instrument 70 is shown
engaged at its proximal end with the proximal end of the coupling
component 20 and is engaged at its distal end at a more distal
locus on the coupling component 20 near the proximal end of the
insertion tool 80. Referring now to FIG. 14, upper right panel, the
exemplary embodiment of the tensioning instrument comprises a
handle portion 71 that actuates opposing gripping elements 72
around a pivot axis, whereby actuation of the handle 71 moves the
opposing elements 72 towards and away from one another.
Referring now to FIG. 15, close up detail in the center panel shows
the tensioning tool 70 comprises at its proximal grip element 73 a
clamp actuation sleeve 74 with opposing clamping means extending
therefrom and configured to receive the coupling component 20 in a
central channel defined through the clamping means. The proximal
grip element 73 of the insertion instrument locks onto the coupling
component 20. The tensioning tool also comprises a distal grip
element 75 that engages with and articulates to push down on the
top of the insertion tool 80, which in turn presses on the top of
the locking assembly 40. In use, the instrument grips 72 are
affixed to a coupling component 20 as shown, for example, in the
upper panel of FIG. 15, the tool handle 71 is squeezed by the
operator to rotate the proximal grip element 73 away from the
distal grip element 75, thereby actuating upward movement of the
proximal end of the coupling component 20. This motion causes the
lower grip element 75 of the tool 70 to displace downward into
contact with the proximal end of the inner sleeve 81 of the
insertion tool 80. Repeated squeezes of the handle 71 further
actuate gripping and upward displacement of the coupling component
20, thereby driving the inner sleeve 81 of the insertion tool 80
assembly and locking assembly 40 distally, and forcing the distal
end of the collet 50 against the proximal bone. The effect of
actuation of the insertion instrument 80 is to reduce the two or
more bone elements (i.e., compress them against one another
effectively reducing the space there between) and at the same time
reduce the clearance between the distal end of the locking assembly
40 and the proximal bone. Tensioning is complete when the collet 50
at the distal end of the locking assembly 40 is firmly pressed
against the bone. The tensioning tool 70 handle 71 is locked to
maintain tension on the coupling component 20 while the locking
assembly 40 is engaged and secured. Engagement of at least one side
pin 83 of the insertion instrument enables securement of the inner
sleeve to the outer sleeve of the insertion instrument, and
downward compression on the insertion instrument drives engagement
and final closure of the locking assembly 40.
It will be appreciated that the instruments described herein are
merely representative, and that more or fewer instruments
comprising the same features may be provided. Thus, in some
embodiments, the features of one or more of the tensioner,
insertion tool, and reducer may be integrated into a single
instrument. Alternately, in other embodiments, the components of
the instruments may be modular, such that, for example, the sleeves
of the insertion tool may be sequentially assembled, or they may be
provided in combination with the locking assembly such that the
operate need only slip the locking assembly/insertion and reducer
assembly on to the coupling component without the need to assemble
them in series.
The instruments, and the coupling component and one or more
components of the locking assembly may be formed out of any
suitable biocompatible material and combinations thereof, including
those used conventionally in the art. Such materials include but
are not limited to: metals such as, for example, stainless steel
(such as 316 LVM, per ASTM F1350, electropolished and passivated),
titanium alloys (such as TI-6AL-4V, per ASTM F136), cobalt alloys,
superelastic metals, such as nitinol; polymers, such as polyester
and polyethylene, polyether ether ketone (PEEK); and resorbable
synthetic materials such as, for example, suture material and
polylactic acid.
Example 4: Threaded Torsional Locking Compression Fixation
System
Referring now to FIG. 16-FIG. 18, various views of an alternate
embodiment of a compression fixation system 10' are shown. FIG. 16
shows a side view of a fully assembled compression fixation system
10' engaged with coupling component 20' tensioning and locking
assembly 40' inserter instruments.
The compression fixation system 10' includes a coupling component
20' that is selected from suitable wire and other bone pins and
similar rod type devices, such as, for example K-wire. The coupling
component 20' is adapted at a distal first end 21', intended to be
most distal to the operator, with an anchor portion 23' for
fixation within or on a distal outer surface of a first bone
element. The coupling component 20' is further adapted at a
proximal second end 22', intended to be most proximal to the
operator, with a locking assembly 40' receiver portion 24' that is
generally rectilinear. In various embodiments, at least the
proximal second end 22' portion of the coupling component 20' is
substantially rectilinear, and cylindrical, while the distal and a
medial portion of the coupling component 20' may be other than
rectilinear or may be initially rectilinear and manipulated by the
operator for optimal engagement and shape conformity with the two
or more elements to be fixed.
The distal anchor portion 23' of the coupling component 20' may be
selected from any of a number of anchors known in the art, and
generally selected from (i) those that are adapted to engage with
and remain substantially within and anchor to a bone, and (ii)
those that extend through bone and are adapted to engage with an
outer surface of a bone or bone fragment, or a plate or other
non-bone material that is intended to be held adjacent to the
distal bone element. Some examples of anchors that are adapted to
engage with and remain substantially within and anchor to a bone
include self or non-self tapping threads, and bone engagement
features that can engage by press fitting such as keels, ribs and
fins. Some examples anchors that extend through bone and are
adapted to engage with an outer surface include coils, barbs, and
toggles.
Referring again to the drawings, enlarged views of the distal
portion of an exemplary embodiment of a coupling component 20' are
shown in FIG. 16. As depicted, the anchor is a toggle anchor 30',
which is pivotal around an axis that is perpendicular to a long
axis of the coupling component 20'. FIG. 16 lower left panel shows
a side view of the deployed toggle anchor 30', and FIG. 16 lower
right panel shows a distal to proximal end perspective view of a
deployed toggle anchor 30'. In an insertion configuration, the
toggle anchor 30' is pivoted so that it is aligned with the long
axis of the coupling component 20' to enable insertion into the
bone and allow clean exit from a proximal end of the bone.
Actuation of the pivot feature of the toggle anchor 30' rotates its
position so that it is perpendicular to the axis of the coupling
component 20', and is deployed to operate as an anchor, thereby
preventing back out of the coupling component 20' from the bone.
While the toggle anchor 30' as shown is engaged with the coupling
component 20' in a split end configuration, one of ordinary skill
will understand that the toggle anchor 30' may be attached by any
one of other possible means, such as a cantilever attachment to one
side of the coupling component 20', as described herein above, and
as shown in other drawings, specifically FIG. 10 and FIG. 20.
One of ordinary skill will appreciate that the depicted coupling
component 20' can be provided in variable lengths, with or without
curves or bends, with or without surface texture and surface
features. Moreover, while the depicted coupling component 20' is
generally cylindrical in shape from the proximal end and terminates
at the exemplary anchor, one of ordinary skill will appreciate that
the shape may be other than cylindrical (i.e., the cross section
may be other than circular). Thus, in some alternate embodiments,
the coupling component 20' may have a cross section that is
selected from one of the following non-limiting examples,
including, scalloped, star shaped, hexagonal, square, and ovoid.
Likewise, the coupling component 20' may be uniform in cross
sectional shape and width along its entire length, or it may
comprise regions that vary and include combinations of different
cross sectional shapes, widths/diameters, and textures. Thus, it
will be appreciated that any particular region which may be
substantially rectilinear for receiving a locking assembly 40' may
be cylindrical or otherwise shaped and may be smooth or have any
one of a variety of surface features such as grooves or notches and
textures that comprise knurling or other non-smooth texturing.
Further, while the exemplary embodiment of the coupling component
20' shown in the drawings terminates as a cylinder at the proximal
end, there may be alternate shapes and features at the proximal end
that are suited for engagement with a tool or instrument. Thus, in
some non-limiting examples, the coupling component 20' may comprise
at its proximal end a hemispherical, conical or frustoconical
feature, or a star, scallop or hex cross-section, or combinations
of these.
In some alternate embodiments, the coupling component 20' may have
a diameter that permits cannulation through at least a portion of
the coupling component 20'. In some examples such embodiments would
include cannulated bone wires and pins. In other such embodiments,
examples include tubes, conduit, pipes, and other substantially
hollow components that are suitable to receive a locking assembly
40' along at least a portion of the component that is
rectilinear.
The compression fixation system 10' also comprises a locking
assembly 40'. Referring again to FIG. 17 lower right panel, a side
view of a representative embodiment of a locking assembly 40' is
shown inserted on and arranged concentrically with the coupling
component 20'.
The exemplary embodiments of the locking assembly 40', as shown in
the drawings, includes inter-engaging collet 50' (left), collet
seat 55' (middle), and compression nut 60' (right) components,
shown, respectively, in side and cut away views in FIG. 17 upper
and middle panels. Referring now to FIG. 17 upper and middle
panels, each of the compression nut 60', collet 50' and collet seat
55' components cooperate along a shared axis and inter-engage to
form a locking assembly 40'. As shown, the assembled locking
assembly 40' components form a channel there through for receiving
a coupling component 20' to achieve locking fixation with the
coupling component 20'.
The collet seat 55', collet 50' and compression nut 60' components
are constructed to slide over at least a distal first end 21' of
the coupling component 20' while in an open configuration, can be
held stably on the coupling component 20' in a friction (engaged
but not locked) configuration to enable positioning relative to the
elements to be fixed, and can be actuated to achieve a locked
configuration. FIG. 17 lower left panel shows an exemplary locking
assembly 40' assembled with the coupling component 20' inserted
through the central bore. As shown, the collet seat 55' is depicted
as transparent to show the relative inter-fitting between the
compression nut 60', collet 50', and collet seat 55' components.
The collet seat 55' and collet 50' have complimentary engagement
surfaces that inter-fit and are adapted with features to enable
precise locking and prevent sliding and rotation relative to the
coupling component 20'. Likewise, again with reference to FIG. 17,
the compression nut 60' and the collet 50' have complementary
engagement surfaces that also inter-fit and are adapted to enable
secondary locking to prevent sliding and rotation relative to the
coupling component 20'. An advantageous aspect of this system is
that the connection and compression can be achieved without
introduction of rotational insertion to the system; that is, the
collet seat 55' and collet 50' are designed to engage with the
compression nut 60' without rotating around the shared axis with
the coupling component 20', thereby diminishing the risk of
material stripping into patient tissue and ensuring optimal
compression and purchase of the coupling component 20' surface. In
various embodiments, the compression fixation system 10' may be
provided for use by an operator in a pre-assembled state,
completely disassembled, or in a state of sub-assembly.
Referring again to FIG. 17, the collet seat 55', as depicted, is
generally frustoconical, with a central bore that is substantially
cylindrical at its most distal end, and proximal to the cylindrical
portion a distal interior wall that is frustoconical in shape and
adapted to receive and inter-fit with the collet 50' when the
collet 50' is inserted therein. The collet seat 55' also has a
substantially cylindrical and threaded proximal interior wall 56'
for inter-engagement with the compression nut 60'. The interior
surface of the collet seat 55', as depicted, is generally smooth at
the distal seat 58' and the seat 58' is generally conical in shape.
The exterior surface of the collet seat 55' is tapered and
generally smooth from the proximal 57' to the distal end 59', and
includes on its proximal end 59' an instrument engagement feature
61'. The collet seat 55', as depicted, includes a hex nut
configuration at its proximal end for engagement with a positioning
and locking instrument. It will be appreciated by those skilled in
the art that other engagement features are possible and that the
disclosed engagement feature is not to be limiting. In alternate
embodiments, all or a portion of the exterior surface as well as
the interior surface of the collet seat 55' may be textured by
surface treatment or other features such as ridges, grooves, keels,
fins, thread, dimples and the like to enhance engagement with and
locking between the collet seat 55' and the collet 50'. Likewise,
the shape of the interior distal wall 58' of the collet seat 55'
may have a shape that is other than conical, for example, it may be
hemispherical.
In alternate embodiments, the collet seat 55' extends distally to
form a sleeve that extends along at least a portion of a coupling
component 20' that is inserted there through. Referring to the
drawings, FIG. 10 and FIG. 20 depict some such embodiments. Of
course, in yet other embodiments, the distal end of the collet seat
55' may extend along substantially all of the length of the
coupling component 20'. In some such embodiments, a further locking
component (not shown) may be provided that attaches to the distal
end of the coupling component 20' and extends proximally to receive
and engage the distal end of the elongate sleeve end of the collet
seat 55'. In yet other embodiments, the extended sleeve closely
contacts the surface of the coupling component 20' providing
enhanced locking engagement therewith. According to such specific
embodiments, the extended sleeve may be adapted with a taper to
allow insertion into the proximal fixed element. In such case where
the element is bone, the tapered distal end of the collet seat 55'
sleeve may be inserted into the bone to further enhance fixation
and securement to the bone. Optionally, the distal sleeve may have
on its exterior surface features or texture that further enhance
engagement with bone, particularly when the taper is inserted
therein.
Referring again to FIG. 17, the collet 50', as depicted, is
generally cylindrical, having a central bore that is cylindrical
and adapted to receive the coupling component 20', a tapered distal
end that is generally frustoconical a tapered proximal end, and a
series of slots 51' that are generally equally spaced
circumferentially, and, as depicted, alternate in origination from
the proximal 52' and distal ends 53'. It will be appreciated that
the slots may, in alternate embodiments, be unequally spaced, there
may be fewer or more slots, and they may all originate from one or
the other of the proximal and distal end. As depicted, the collet
50' has a circumferential groove or channel that is distal of the
midpoint of the collet 50' and defines the boundary between the
tapers of the proximal 52' and distal ends 53', referred to herein
as the proximal lobe and the distal lobe, respectively, of the
collet 50'. The proximal lobe 54' of the collet 50' is shaped to
inter-fit with the interior surface 62' of the compression nut 60'.
The distal lobe of the collet 50' is shaped to inter-fit with the
interior distal wall 58' of the collet seat 55'. The exterior
surface of the collet 50', as depicted, is generally smooth on each
of the proximal and distal lobes. In alternate embodiments, all or
a portion of the exterior surface as well as the interior surface
of the collet 50' may be textured surface treatment or other
features such as ridges, grooves, keels, fins, thread, dimples to
enhance engagement with and locking between the distal end of the
collet 50' and the collet seat 55', and between the proximal end of
the collet 50' and the compression nut 60'.
Advantageously, referring again to FIG. 17, the two lobed design of
the collet 50' enables uniform compression along its length and
enhanced compression circumferentially against the coupling
component 20' inserted there through as a result of the combined
compressive force of the collet seat 55' on the distal lobe of the
collet 50' and the compressive force of the compression not on the
proximal lobe of the collet 50'.
Referring again to FIG. 17, the compression nut 60', as depicted,
has a tapered cylindrical interior 62' surface, which is
complementary to the taper of the proximal lobe of the collet 50'.
The compression nut 60' has a substantially cylindrical exterior
63' surface with threading 64' at the distal end for engagement
with the proximal interior wall 56' of the collet seat 55', and
includes on its proximal end an instrument engagement feature 65'.
The compression nut 60', as depicted, includes a hex nut
configuration at its proximal end for engagement with a positioning
and locking instrument. It will be appreciated by those skilled in
the art that other engagement features are possible and that the
disclosed engagement feature is not to be limiting. Likewise, it
will be appreciated that the interior surface of the compression
nut 60' may have an inverted taper or no taper at all, and it may
have surface texturing or other treatment or features as disclosed
herein to enhance engagement with the coupling component 20'. And
in alternate embodiments, all or a portion of the non-threaded
exterior surface of the compression nut 60' may be textured with
surface treatment or other features such as ridges, grooves, keels,
fins, thread, dimples to enhance engagement with and locking
between the proximal end of the compression nut 60' and a feature
that is proximal thereto.
As described herein above, various instruments are provided that
facilitate use of the compression fixation system 10' components.
One exemplary instrument includes a tensioning grip that clamps the
coupling component 20' to stabilize it and enable maintenance of
tension during locking assembly 40' locking, as shown in FIG. 1 and
FIG. 16.
Another exemplary instrument includes a locking assembly 40'
counter torque insertion tool 80'. The counter torque insertion
tool operates to maintain orientation and alignment of the locking
assembly 40' components and the coupling components 20' and can be
actuated to reduce and lock the locking assembly 40' components, or
loosen and unlock the locking assembly 40' for adjustment during
healing or post treatment removal of the system. Referring again to
the drawings, FIG. 18 depicts an alternate exemplary embodiment of
a locking assembly 40' tool, namely a counter torque insertion tool
80' for achieving placement, component reduction, friction
tensioning, locking and unlocking of a locking assembly 40' as
described herein. Referring now to FIG. 18, the counter torque
insertion tool 80' includes two nesting elongate sleeves 81', 82',
each having a substantially cylindrical interior, the inner sleeve
81' having an internal and external cylindrical shape and
dimensioned to closely interfit with the interior cylindrical
interior of the outer sleeve 82'. As depicted in FIG. 18 upper and
lower right panels, cutaway views of the outer sleeve 82' show that
the counter torque insertion tool 80' includes opposing pins 83'
that are press fit into the outer sleeve 82'. These pins constrain
the outer sleeve to the inner sleeve via the pins engaging a
groove. The outer sleeve 82' is able to freely rotate about the
inner sleeve. The outer sleeve can also translate to relative to
the inner sleeve 81, but only a short distance. This distance
corresponds roughly to the amount of translation needed to engage
the compression nut 60' to the collet seat 55'. FIG. 18 upper left
panel shows a distal end view of the assembly of the counter torque
insertion tool 80' and the locking assembly 40', showing the edges
of the opposing pins 83'.
The depicted locking assembly 40' counter torque insertion tool 80'
is comprised of concentric inner and outer sleeves 81', 82', each
of which sleeves 81', 82' inter-engages with at least a portion of
the external surface of one or more of the collet seat 55', the
collet 50' and the locking nut. Referring now to FIG. 18 lower left
panel, the outer sleeve is adapted with an interior groove feature
that inter-engages with the outer proximal edge of the collet seat
55' to lock it relative to the other components of the system.
Likewise, the inner sleeve 81' is adapted with notches 84' to
inter-engage with corresponding features on the proximal rim of the
compression nut 60'. The engagement there between enables
differential axial rotation of the compression nut 60' by the
counter torque insertion tool 80' while the collet seat 55' is held
in place, thereby driving the mating threads of the compression nut
60' and the collet seat 55' into engagement.
In use, the threads of the collet seat 55' and nut may be partially
engaged to enable friction fixation of the locking assembly 40'
while tensioning is applied to tighten the coupling component 20'
and firmly place the locking assembly 40' against the proximal
element. Upon application of further torsional force to the counter
torque insertion tool 80', the threads of the compression nut 60'
and collet seat 55' are fully engaged, directing circumferential
force against the upper lobe of the collet 50' and forcing the
lower lobe of the collet 50' firmly into the collet seat 55'
thereby locking the lower lobe to achieve locked fixation of the
fattener to the coupling component 20'.
It will be appreciated that the instruments described herein are
merely representative, and that more or fewer instruments
comprising the same features may be provided. Thus, in some
embodiments, the features of one or more of the tensioner, torque
reduction tool and reducer may be integrated into a single
instrument. Alternately, in other embodiments, the components of
the instruments may be modular, such that, for example, the sleeves
81', 82' of the insertion tool 80' may be sequentially assembled,
or they may be provided in combination with the locking assembly
40' such that the operate need only slip the locking assembly
40'/torque and reducer assembly on to the coupling component 20'
without the need to assemble them in series.
While various inventive aspects, concepts and features of the
general inventive concepts are described and illustrated herein in
the context of various exemplary embodiments, these various
aspects, concepts and features may be used in many alternative
embodiments, either individually or in various combinations and
sub-combinations thereof. Unless expressly excluded herein all such
combinations and sub-combinations are intended to be within the
scope of the general inventive concepts. Still further, while
various alternative embodiments as to the various aspects, concepts
and features of the inventions (such as alternative materials,
structures, configurations, methods, devices and components,
alternatives as to form, fit and function, and so on) may be
described herein, such descriptions are not intended to be a
complete or exhaustive list of available alternative embodiments,
whether presently known or later developed.
Those skilled in the art may readily adopt one or more of the
inventive aspects, concepts or features into additional embodiments
and uses within the scope of the general inventive concepts even if
such embodiments are not expressly disclosed herein. Additionally,
even though some features, concepts or aspects of the inventions
may be described herein as being a preferred arrangement or method,
such description is not intended to suggest that such feature is
required or necessary unless expressly so stated. Still further,
exemplary or representative values and ranges may be included to
assist in understanding the present disclosure; however, such
values and ranges are not to be construed in a limiting sense and
are intended to be critical values or ranges only if so expressly
stated. Moreover, while various aspects, features and concepts may
be expressly identified herein as being inventive or forming part
of an invention, such identification is not intended to be
exclusive, but rather there may be inventive aspects, concepts and
features that are fully described herein without being expressly
identified as such or as part of a specific invention. Descriptions
of exemplary methods or processes are not limited to inclusion of
all steps as being required in all cases, nor is the order that the
steps are presented to be construed as required or necessary unless
expressly so stated. Further, while disclosed benefits, advantages,
and solutions to problems have been described with reference to
specific embodiments, these are not intended to be construed as
essential or necessary to the invention.
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